Surface-initiated Polymerization of Mussel-inspired Dopamine for Hydrophilic Coatings

AbstractThe aim of the present study was to design and synthesize a new class of compounds for the softening of hard water, i.e. for the removal of the divalent cations Ca2+ and Mg2+. To that end, a class of alternating aliphatic polyketones (copolymers of ethylene and propylene with carbon monoxide, PK30) was functionalized with a variety of amines employing the Paal-Knorr reaction, a relatively straightforward reaction-route to synthesize functional polyketones. The amino groups included aliphatic and aromatic structures with a molecular weight ranging from 74.1 to 129.2 g/mol. Elemental analysis was used to establish the degree of functionalization, whereas 1H-NMR spectroscopy was used to identify the molecular structure of the prepared polymers. Model compounds were used as reference for guiding structure determination and for studying the (relative) reaction kinetics.

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Synthesis, structure and spectroscopic properties of a novel compound bis(benzylamino)silver(I) benzylcarbamate

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768112030212 ◽

2012 ◽

Vol 68 (4) ◽

pp. 401-406

Author(s):

Jianguo Liu ◽

Xiaoyan Zeng ◽

Hua Li

Keyword(s):

Molecular Structure ◽

Solid State ◽

Hydrogen Bonds ◽

Room Temperature ◽

Silver Oxide ◽

Spectroscopic Properties ◽

Amino Groups ◽

Triclinic Crystal System ◽

Carboxylate Groups ◽

Silver Silver

A novel silver-containing compound, bis(benzylamino)silver(I) benzylcarbamate, with an unusual molecular structure is easily synthesized by the reaction of benzylammonium benzylcarbamate and silver oxide. It crystallizes in the triclinic crystal system with the space group P\bar 1 with a = 5.2006 (5), b = 14.6298 (15), c = 14.7246 (15) Å, α = 68.729 (2), β = 83.507 (2), γ = 85.412 (2)° and Z = 2. In the crystal, one Ag atom coordinates with the two amino groups in two benzylamine molecules, and there are no silver–silver and silver–oxygen interactions. The carboxylate groups take part in balancing the electric charge and forming hydrogen bonds. Both the compound and the starting material benzylammonium benzylcarbamate exhibit room-temperature solid-state emissions with the peaks at 300 and 406 nm, respectively.

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Molecular Structure of the Outermost Cell Wall Component of Spirillum Serpens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079218 ◽

1977 ◽

Vol 35 ◽

pp. 342-343

Author(s):

Wah Chiu ◽

David Grano

Keyword(s):

Molecular Structure ◽

Cell Wall ◽

Outer Membrane ◽

Gel Electrophoresis ◽

Electron Microscopic Examination ◽

Electron Microscopic ◽

Cell Wall Component ◽

Protein Components ◽

Exposure Technique ◽

Structural Aspects

The periodic structure external to the outer membrane of Spirillum serpens VHA has been isolated by similar procedures to those used by Buckmire and Murray (1). From SDS gel electrophoresis, we have found that the isolated fragments contain several protein components, and that the crystalline structure is composed of a glycoprotein component with a molecular weight of ∽ 140,000 daltons (2). Under an electron microscopic examination, we have visualized the hexagonally-packed glycoprotein subunits, as well as the bilayer profile of the outer membrane. In this paper, we will discuss some structural aspects of the crystalline glycoproteins, based on computer-reconstructed images of the external cell wall fragments.The specimens were prepared for electron microscopy in two ways: negatively stained with 1% PTA, and maintained in a frozen-hydrated state (3). The micrographs were taken with a JEM-100B electron microscope with a field emission gun. The minimum exposure technique was essential for imaging the frozen- hydrated specimens.

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Aldehyde gold clusters for molecular labeling

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014066x ◽

1995 ◽

Vol 53 ◽

pp. 858-859

Author(s):

James F. Hainfeld ◽

Frederic R. Furuya

Keyword(s):

Covalent Bond ◽

Aldehyde Group ◽

Gold Clusters ◽

Side Reactions ◽

Amino Groups ◽

Sodium Cyanoborohydride ◽

Schiff’S Base ◽

Protein Molecules ◽

Hydroxysuccinimide Esters ◽

Primary Amino

Glutaraldehyde is a useful tissue and molecular fixing reagents. The aldehyde moiety reacts mainly with primary amino groups to form a Schiff's base, which is reversible but reasonably stable at pH 7; a stable covalent bond may be formed by reduction with, e.g., sodium cyanoborohydride (Fig. 1). The bifunctional glutaraldehyde, (CHO-(CH2)3-CHO), successfully stabilizes protein molecules due to generally plentiful amines on their surface; bovine serum albumin has 60; 59 lysines + 1 α-amino. With some enzymes, catalytic activity after fixing is preserved; with respect to antigens, glutaraldehyde treatment can compromise their recognition by antibodies in some cases. Complicating the chemistry somewhat are the reported side reactions, where glutaraldehyde reacts with other amino acid side chains, cysteine, histidine, and tyrosine. It has also been reported that glutaraldehyde can polymerize in aqueous solution. Newer crosslinkers have been found that are more specific for the amino group, such as the N-hydroxysuccinimide esters, and are commonly preferred for forming conjugates. However, most of these linkers hydrolyze in solution, so that the activity is lost over several hours, whereas the aldehyde group is stable in solution, and may have an advantage of overall efficiency.

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Morphogenetic machines revealed: Microscopy of living cells in the embryo of the frog, Xenopus laevis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146709 ◽

1993 ◽

Vol 51 ◽

pp. 172-173

Author(s):

Ray Keller

Keyword(s):

Image Processing ◽

Fluorescent Dyes ◽

Cell Movement ◽

Living Cells ◽

Ease Of Use ◽

Low Light ◽

Amphibian Embryo ◽

Large Populations ◽

Light Fluorescence ◽

Video Image Processing

The amphibian embryo offers advantages of size, availability, and ease of use with both microsurgical and molecular methods in the analysis of fundamental developmental and cell biological problems. However, conventional wisdom holds that the opacity of this embryo limits the use of methods in optical microscopy to resolve the cell motility underlying the major shape-generating processes in early development.These difficulties have been circumvented by refining and adapting several methods. First, methods of explanting and culturing tissues were developed that expose the deep, nonepithelial cells, as well as the superficial epithelial cells, to the view of the microscope. Second, low angle epi-illumination with video image processing and recording was used to follow patterns of cell movement in large populations of cells. Lastly, cells were labeled with vital, fluorescent dyes, and their behavior recorded, using low-light, fluorescence microscopy and image processing. Using these methods, the details of the cellular protrusive activity that drives the powerful convergence (narrowing)

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